Tube-bending machine.



L. H. BRINKMAN TUBE BENDING MACHINE. APPLICATKON FILED MAY 26. I913.

Patented Jan. 2', 1917 2 SHEETS-SHEET l.

L. H. BRINKMAN.

TUBE BENDING MACHINE. APPLICATION FILED- MAY '26. 1913.

Patehted Jan. 2,1917.

2 SHEETS-SHEET 2- M MW;

IIVI/EIVTOR,

-ddf /iy w w .4 TTORA/EVJ LOUI$ K. BRENKMAN, 013 GLEN RIDGE, NEVI JERSEY, AS SIGNOR, BY MESNE ASSIGR MEETS, T BALTIMORE TUBE COMPANY, INCORPORATED, A CORPORATION OF VIR- srnra.

Specification of Letters Patent.

'iUBE-BENDING MACHINE.

Patented Jan. 2, 1%17.

Application filed May 26, 1913. Serial No. 769,835.

To all whom it may concern:

Be it known that I, LOUIS H. BRINKMAN, a citizen of the United States, and a resident of Glen Ridge, in the county of Essex and State of New Jersey, have invented new and useful Improvements in Tube-Bending Machines, of which the following is a specification.

An object of my invent-ion is the provision of a tube-bending machine which is.

simple in construction and. which is rapid and automatic in operation.

Another object of my invention is the provision of means whereby the tube to be bent may be easily, quickly and reliably attached to the former around which the bending is to be made, and which may also be easily and quickly detached from the former.

Another object of my invention is the provision of improved means whereby the tube may be fed to the former at any desired angle and which means can be adjusted to a given angle and thereafter remain at that angle for an indefinite number of cycles.

My invention consists of a method and apparatus for attaining the above and many other objects and results, .as will appear from the following description taken in. con- A ncction with the attached drawings, 1n

which Figure 1. is a plan view of the machine, complete; Fig. 2 is an elevation of the machine; Fig. 3 is a section on line 33, Fig. 1; Fig. 4 is a view of the means for attaching the pipe to the former: and Fig. 5 1s a section on line 5-5 of Fig. 1.

For convenience my machine may be con sidered as comprising the following: (1) a former on which the tubes are to be bent; (2) means for attaching the tube to the former so that it may be bent; (3) means for guiding and holding the tube in proper relation to the former; (4) means for driving the former, etc; and (5) means for reversing the driving means so as to automatically discharge the bent tube from the former and put the machine in condition for the reception of another tube.

The machine comprises a frame member 1 in which are mounted the shafts 2 and 4 in suitable bearing blocks. On the shaft 2 are mounted pulleys 3 and 3 arranged with a clutch device 5 so that the shaft 4 may be driven in opposite directions. On the shaft 2 is a pinion 6 which meshes with a gear 7 mounted on the shaft 4. The shaft l carries at its left end a flange 8 which may be attached to said shaft in any well-known manner. The flange 8 is provided with bolts, or other means, adapted to receive a corresponding flange member 9 carried on the end of a former 10. The former 10 may be of any desired diameter or length, and may be provided with suitable spirals or threads 11. and of any pitch desired so that when a tube is bent thereon it will have the desired formation.

The guide shown in Fig. 3 is adapted to be carried on the former 10. This guide comprises a member 12 having a projection 13 and a curved portion adapted to codperate with the former 10, as clearly shown in Fig.3. A bolt 14: passes through the member 12 of the guide and has a head 15 which engages a swiping-block 16 which is pro vidcd with a groove so as to engage the whole lower half of the pipe 17 which is being operated upon, as shown in Fig. 5. By means of the screw 14 and the hand-wheel 18 any desired pressure can be had between the swiping-block, the pipe and the underside of the former so that the proper tension will be placed on the tube to get a smooth bend. In the projection 13 of the member 12 is mounted a set screw 19 provided with a lock-nut 20. The set screw 19 can be adjusted so as to accommodate the guide to formers of different diameter. The

former when considered from'the main body This is useful in maintainof the guide.

ing the proper position of the guide with regard to the former but it is not essential in the bending operation because the friction between the tube, the guide and the swiping-block is sufficient to keep the guide in position. In the the tube from the former, as more specificallv described hereinafter, this may be useful in preventing the guide from being moved back away from the former. A screw having a hand-wheel 21 is provided, preferably at right angles to the bolt 14, so that the proper forward position of guide may be adjusted in order that the mandrel 22 will be in proper position with automatic discharge of the being bent, it is desirable to have means which may be adjusted to any desired angle,

' and after being adjusted will remain at that angle until readjusted. I have, therefore, devised means to that end which are shown in Fig. 1. For the purpose of supporting the mandrel with the tube thereon so that they Jwill not sag I placethe mandrel and the tube in a V-shaped trough 25 of any suitable material, such as ordinary angle-iron. One end of the trough is supported by a frame of any suitable construction such as that-shown in Fig. 1 and which consists of standards 26 having a track-way 27 upon which rollers, or other suitable means may run. On the outer track-way is carried one end of the trough into which the mandrel and tube are placed. The end of the trough 25 near the former is attached to the swiping-block 16 by any means such as the screws 29, and is carried thereby, as shown in Fig. 5. By reference to Fig. 5 it will be seen that the swiping-block 16 has a groove in its upper surface which fits a pipe of a given diameter. A given swiping-block is used with tubes of one diameter so that when it is desired to bend tubes. of a different diameter another swiping-block will preferably be used. The swiping-block is also grooved 0 receive the trough 25 so that the tube will bear against the sides of the trough until it passes out of v the trough and it Will then bear against the bottom of the roove in the block 16 without changing its e evation. The frame near the former has no function in supporting the trough during the operation of the machine but forms a support for the pulleys 32 and 35 around which the cable 31 passes as explained hereinafter. At points onthe swiping-block 16 are attached the ends 30 of a suitable cord, such as a wire cable 31-. This cable is then carried around pulleys 32, 33, a pulley not shown on the drawing and pulley 35. from the former is provided a clamp 36 of any suitable character forattaching that end of the trough to the cable 31. This clamp is adjustably mounted in a'slot 34 so that it may be put in position to grasp the cable 31 at any angle Which the trough may be placed.

From the above description it will be seen that when the trough and the mandrel are put in position and clamped both ends of the tube and mandrel will travel longitudinally of the former at the same rate of speed. If

'tion 'of the cable any desired pitch.

At the end of the trough away the movement is to be from the outer end of the former toward the flange, or inner end it will be seen that as the inner end of the trough is carried alon by the guide, stress will be put on the cab e passing around the pulley 32 and communicated through that 'port1on going around the pulley 33 and to the clamp 36 which is rigidly connected-with the outer end of the trough whereby the trough, as a whole, will be moved at a fixed angle to the former. It is noted, of course, that the movement of the trough in the. direction indicated will tend to release the porpassing around pulley 35 so'tha-t the outer end of the trough is permitted to move-at-the proper speed. This insures a proper angular relation of the tube to the former-.i It also makes it ossible to feed the tube at any angle to the ormer desired so that tubes may be bent or coiled at Attached to the swiping-block 16 is a member 37 having an extended slot 38 near one end thereof. Mounted in the slot is a pin 40. This pin is attached to an arm 41 which controls the driving clutches 42 and 43, whereby the direction of rotation of the former 10 is controlled. The clutching apparatus may be of any Well-known type and is illustrated only diagrammatically in the'drawings. As will be seen from Fig. 1 this clutching mech-- anismis controlled indirectly by the former so that when properly adjusted the direction of rotation of the former 10 will be such as to coil up the tube and soon after the coiling operation is finished the direction of rotation of the former will be reversed and the tube automatically discharged. In this embodiment of the invention the above operation is effected through the members 37 and 41., The member 41 is pivoted at 44 and carries a roller 45 adapted to roll on the cam surface of a member 46. The roller is pressed downward by a spring 47. The operation of these devices will be more fully explained later. j

It has been the practice heretofore in this art to clamp the tube to be bent around the outside by a" clamp which may then be attached to the former'so that the tube would be held. on the former during thebending operation. All suchmeans known to meare inefiicient and wasteful in many wa s. It is found in practice that in using a clamp of the character heretofore employed the operator fails in some instances to get the proper grip on the tube so that durmg the bending operation the tube would slip. in the clamp, or come entirely out of the clamp, and as a result the tube would have to be scrapped. The waste due to this means of attacling thetube has been found toentail of the former,

Laioeea remove the tube from the machine. The at tachment of the tube to the mandrel by these devices takes a great deal of time and also a considerable length of tube must be placed within the clamp in order to secure the same that portion of the tube necessary for at-- taching the finished product to its fixture is unbent and none of the tube wasted.

My device is shown in Fig. 4, and consists of a single member 48. This member is of the general shape of the letter C. It has a straight portion 49 which is adapted to enter the inside of the tube, and a portion 50 adapted to enter a recess in the former or it may be hooked over a flat portion of the end member is preferably eccentric to the former so that when the former is rotated with the device attached to a tube and the former, pressure will be exerted on the former at the point 50 and on the inner surface of the tube at the point 49 thus creating pressure between the inside of the tube and the former when the former is rotated in one direction. The same result would be accomplished if the former were stationary and the tube carried around the former. This causes the tube to be held securely between the member 48 and the former. The member 48 is preferably made in a spiral shape so as to lie within the spirals on the former. It is not necessary that the curved portion of the member be eccentric to the former except when the member is in position on the former. That is to say, that the member might be concentric with the former when it is not in place Within the end of a tube, but when the member is placed within a tube the thickness of the tube between one end of the member and the former will cause it to assume an eccentric position, thus securing a reliable attachment of the tube to the former when relative movement is produced between the former and the tube in one direction.

The operation of my machine is as follows: The former being at a standstill, the guide with the mandrel is placed near the outer end of the former. The member 48 is then placed in the end of the tube to be bent, thus forming a handle by which the tube can be placedon the mandrel, as shown in Fig. 4. At this time the mandrel is in its extreme backward position, as shown in Fig. 4. The outer end of the stem 24 of the mandrel is provided with screw-threads and nuts 51 and are placed thereon so that the position of the mandrel with regard to the bending point of the tube can be adjusted and maintained. The outer end of the mandrel.

as shown in- Fig. 4. This.

trough is provided with a slot through which the stem 24 passes. The nuts 51 and 52 are placed on the stem to limit its longi' tudinal movement. The movement allowed the stem by the nuts 51 and 52 is such that the mandrel may be'moved back from the former a distance sufiicient to allow necessary clearance between the upper side of the ball member 23 and the lower side of the former, so that a tube can be slid onto the The angular position of the trough to the former is then adjusted and the clamp 36 fastened onto the cable 31.

The tube is slipped onto the mandrel as shown in Fig. 1, the hook placed in position on the mandrel, the swiping-block 16 is adjusted to give the proper pressure on the underside of the tube, and the lever 41 is moved by the handle 53 to start the former in the proper direction. As the former begins to rotate the member 48 will grip the tube and carry it around with the former. The friction of the mandrel against the inside of the tube will cause it to move up to the position shown in Fig. 3 and the bending will begin in the well-known way. The position of the nut 51 is such that the mandrel is held in the position shown" in Fig. 3. As the former rotates, the guide will be carried longitudinally of the former at a speed dependent upon the pitch of the former, and at the same time the swipingblock 16 will be moved, and by means of the attached cable 31, as hereinbefore explained, both ends of the trough with the mandrel and tube mounted therein will move at the same rate of speed as the guide whereby the tube is fed to the former at a constant and predetermined angle. As the guide, with its attached members, moves toward the inner end of the former the member 37 will be moved to the right. The slot 38 being of the proper length thelever 41 will not be moved until the member 37 at one end of the slot 38 strikes the pin 40 and pushes the arm 41 over the cam surface of the member 46. This will take place a short time after the tube has been completely wound upon the former. The spring 47 will cause the lever 41 to move rapidly over the cam surface of the member 46 in this-direction whereby the clutch member 42 will be released and the clutch member 43 thrown in. The direction of the rotation of the former will then be reversed and the end of the bent tube will revolve with the former until it is caught by the ball 23 on the mandrel 22. This will arrest the movement of the tube through its entire length, tend to other end of the slot 38 and the clutch mechanism moved to an intermediate position whereby the former is stopped. The clutch does not engage in this position because the roller runs on the horizontal surface of the member 46 and it can be stopped at any desired point. In order that different lengths of tube may bebent on the former and the bending be complete before the clutch is operated and the former reversed, I have provided a hand-screw 39 to adjust the relative position of the slot 38 and the pin 40 in the member 41. The machine is then in a position to receive another tube which is attached in the manner hereinbefore described.

I claim- 1. In a. tube-bending machine the combination of a grooved former having a thread thereon, a guide mounted on said former and movable longitudinally of said former at a rate of speed dependent upon the pitch of the thread on the former, a mandrel for the tube one end of which is carried by said guide and means for carrying and moving the other end of said mandrel at the. same relative rate of speed as the guide.

2. In a tube-bending machine the combination of a grooved rotatable former having a" thread thereon, a guide. for the tube carried by the former, a mandrel for the tube, one end of which is carried by said guide, a cable for moving the other end of said mandrel so that the angle between the longitudinal axis of the mandrel and that of the former, is constant, and a clamp rigidly attached to the mandred adapted to engage the cable at different points for maintaining theangle of said mandrel to the former.

3. In a tube-bending machine the combination of a grooved former, a metallic frame cooperating with said former and provided with an adjustable bearing screw disposed to engage the spiral groove in said former,

a bending shoe on one side of the frame, a

mandrel and means whereby said mandrel may be adjusted at any angle to said former and maintained at that angle throughout a' complete bending cycle.

4. In a tube-bending machine the combination of a grooved former, a frame engaging said former, a swiping-block attached to said frame and having a, groove registering with the groove in the former, a mandrel means for moving said mandrel, frame and swiping-block longitudinally of said former in one direction and means for automatically reversing said first-named means after the v bending operation and discharging said tube from the former.

5. In a tube-bending machine, the combination of a grooved former for the tubes to be bent, said former havinga part near the commencement of the groove adapted to be. engagedby a tube-securing member, and

the diameter of the groove adjacent said member.

6. In a tube-bending machine the combination of a former for the tube and means for fastening said tube to said former comprising a member one end of which is adapted to enter the end' of the tube, and the other end to enter a recess in the former.

7. In a tube-bending machine the combination of a former for the tube and means for fastening said tube to said former comprising a single member one end of which is adapted to enter the end of the tube, and the other end to enter a recess in the former.

8. In a tube-bendin machine the combination of a rotatable ormer, means for rotating said former to bend a tube around the same and means for fastening-the tube to the former which consists in a single element one end of which enters the tube and the other end of which enters a recess in said former whereby pressure is created between the inside of the tube and the former when the former is rotated.

9. In a tube-bending machine the combi nation of a former, means for producing relative movement between the tube to be bent and said former and means for fastening the end of said tube to said former having a portion adapted to enter the end of said tube and a ortion to enter a recess in said former where y pressure is created between the inside of the tube and the former when relative movement is produced between the tube and the former in one direction.

10. In a tube-bending machine, in combination, a spirally grooved rotatable former, a metallic frame adjacent said former and arranged to travel backward and forward on said former, it being automatically propelled by engagement with the groove in the former, a grooved bending shoe on one side of said frame, the groove in the shoe always registering with the groove in the former at the bending point, a mandrel attached to and traveling with the bending'shoe, and

misses.

frame, and means to adjust said shoe to the proper angle and clamp it securely in position, and a mandrel and mandrel holder.

12. In a tube-bending machine, in combination, a spirally grooved former a metallic carriage applied to said former and auto matically guided and controlled by it, a

grooved bending shoe on one side of said carriage and adapted for lateral adjustment relative to the former, and a flexible mandrel supported on said shoe, said mandrel having means for moving its outer end at the same rate of speed as the carriage, substantially as described.

13. In a tube bending machine, in combination, a spirally grooved rotatable former, a grooved bending shoe held adjacent to the former at the bending point where the tube receives its initial bend, a mandrel for the tube, a mandrel holder attached to said shoe and movable with the same, andmeans causing relative motion between the bending shoe and the "former in a plane parallel to the surface of such former, as described.

1 In a tube-bending machine, the combination with v a spirally grooved rotatable former, of a carriage adapted to traverse said former, the same comprising a frame adjacent the former, adjustable means connected with said frame and bearing in the groove and adapted to travel in-the same, a grooved tube guide attached to said frame, and means for securing it at any desired lateral inclination to the axis of the former, as described.

15. In a tube-bending machine, the combination with a spirally grooved rotatable former, of a carriage adapted to traverse said former, the same comprising a frame adjacent the former, adjusting s'et-mrews passing through the frame and bearing in the groove at several points and adapted to travel in the groove, a tube guide attached to the lower portion ofsaid frame and extending beneath the former, means for securing it at any desired lateral inclination to the axis of the former, a device for clamping in lateral adjustment, means connectpelled by ed withthe tube guide to draw the same laterally, and means for supporting the rear end of the tube guide while permitting lateral traverse of the same, as described.

16. In a tube-bending machine, in combination, a spirally grooved rotatable former, a metallic frame having means for maintaining a substantially fixed relation between said frame and the longitudinal axis of said former and arranged to travel backward and forward on said former, it being proengagement with the groove in the former, a grooved bending shoe on one side of said former, the groove in the shoe always registering with the groove in the former at the bending point, and a mandrel attached to and traveling with the bending shoe.

17. In a, tube-bending machine, in combination, a spirally grooved former a metallic frame adjacent said former and provided with adjustable bearing screws disposed to engage the spiral groove in said former, a grooved bending shoe on one side of the frame, means whereby said shoe may be adjusted to the proper angle and held securely in position, a mandrel for the tube, a mandrel holder and means for moving the rear end of said holder so .as tomaintain the angle of the :tormer and mandrel.

18. In a tube-bending machine, the combi nation of a grooved rotatable former, a frame adapted to move longitudinally of said former, a grooved bending shoe attached to said frame, a mandrel and means whereby the angle of said mandrel and said former may be adjusted and maintained and both ends of said mandrel positively driven in the same direction and at the same speed which is dependent upon the speed and pitch of said former.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribin witnesses.

LOUIS H. BRINKMAN.

Witnesses:

Nnwron A. "Bonuses, Enwin 

